Pinus squamata X. W. Li, a recently-described species of the Pinaceae, is an extremely endangered pine with only 32 individuals in the wild. This species was thought to be intermediate between P. bungeana Zuec. ex End...Pinus squamata X. W. Li, a recently-described species of the Pinaceae, is an extremely endangered pine with only 32 individuals in the wild. This species was thought to be intermediate between P. bungeana Zuec. ex Endl. of subgen. Strobus and P. yunnanensis Franch. of subgen. Pinus by the original author. We made an effort to address the question of the phylogenetic relationship of this peculiar and important species in the context of the major groups of the genus Pinus by using sequences of the rbcL, matK,genes, rpl20-rps18 spacer, trnV intron of the chloroplast genome and the nuclear ribosomal ITS region. The results of the separated analysis and the combined analysis of the four cpDNA sequences and ITS sequence indicated that P. squamata was a stable member of subsect. Gerardianae and P. gerardiana Wall. was the closest species of P. squamata phylogenetically. As a result, the causes of the distribution pattern of subsect. Gerardianae were also discussed.展开更多
[Objective] The study aimed to analyze the ITS sequences of nrDNA from Rhodiola alisa and investigate the difference of evolution rate between nrDNA and trnS-trnG and rpl20-rps12 sequences of cpDNA(chloroplast DNA).[M...[Objective] The study aimed to analyze the ITS sequences of nrDNA from Rhodiola alisa and investigate the difference of evolution rate between nrDNA and trnS-trnG and rpl20-rps12 sequences of cpDNA(chloroplast DNA).[Method]Total DNA was extracted from silica-dried leaves of R.alsia by using modified CTAB method.With the extracted DNA sample as template,nrDNA ITS region was amplified,then purified and sequenced.In addition,the yielded ITS sequences were also compared with the known trnS-trnG and rpl20-rps12 sequences of cpDNA from R.alsia.[Result]The ITS sequence of nrDNA from R.alsia was 701 bp in length,of which 13 variable sites were found with a percentage of 1.85%.Of the 13 variable sites,8 were caused by point mutations,5 were the results of insertions or deletions.The(A+T)content and(G+C)content were 46.9% and 53.1%,respectively.The nucleotide diversity(π)was 0.004 27.[Conclusion]The ITS region of nrDNA from R.alsia was more conservative and evolved more slowly than the trnS-trnG and rpl20-rps12 sequences of its cpDNA.展开更多
文摘Pinus squamata X. W. Li, a recently-described species of the Pinaceae, is an extremely endangered pine with only 32 individuals in the wild. This species was thought to be intermediate between P. bungeana Zuec. ex Endl. of subgen. Strobus and P. yunnanensis Franch. of subgen. Pinus by the original author. We made an effort to address the question of the phylogenetic relationship of this peculiar and important species in the context of the major groups of the genus Pinus by using sequences of the rbcL, matK,genes, rpl20-rps18 spacer, trnV intron of the chloroplast genome and the nuclear ribosomal ITS region. The results of the separated analysis and the combined analysis of the four cpDNA sequences and ITS sequence indicated that P. squamata was a stable member of subsect. Gerardianae and P. gerardiana Wall. was the closest species of P. squamata phylogenetically. As a result, the causes of the distribution pattern of subsect. Gerardianae were also discussed.
基金Supported by National Natural Science Foundation of China(30170066,30370284)National Basic Research Program of China(2008CB117013)International Foundation for Science(IFSD4258-1)~~
文摘[Objective] The study aimed to analyze the ITS sequences of nrDNA from Rhodiola alisa and investigate the difference of evolution rate between nrDNA and trnS-trnG and rpl20-rps12 sequences of cpDNA(chloroplast DNA).[Method]Total DNA was extracted from silica-dried leaves of R.alsia by using modified CTAB method.With the extracted DNA sample as template,nrDNA ITS region was amplified,then purified and sequenced.In addition,the yielded ITS sequences were also compared with the known trnS-trnG and rpl20-rps12 sequences of cpDNA from R.alsia.[Result]The ITS sequence of nrDNA from R.alsia was 701 bp in length,of which 13 variable sites were found with a percentage of 1.85%.Of the 13 variable sites,8 were caused by point mutations,5 were the results of insertions or deletions.The(A+T)content and(G+C)content were 46.9% and 53.1%,respectively.The nucleotide diversity(π)was 0.004 27.[Conclusion]The ITS region of nrDNA from R.alsia was more conservative and evolved more slowly than the trnS-trnG and rpl20-rps12 sequences of its cpDNA.
